The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations ...The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations one month before the Leshan M5.0 earthquake.展开更多
The epicenter of the M5.0 earthquake occurring in Jinghe County, Xinjiang on October 16, 2011, is located in Tuoli Township. The intensity of the meizoseismal area is VI. The seismic damage investigation shows that th...The epicenter of the M5.0 earthquake occurring in Jinghe County, Xinjiang on October 16, 2011, is located in Tuoli Township. The intensity of the meizoseismal area is VI. The seismic damage investigation shows that the houses are mainly mud-clay style and the seismic damage characteristics take on an obvious regional nature. The damage degree varies relative to the field conditions.展开更多
On the basis of the airgun source signals recorded by the stations from January,2016 to June,2017,we use cross-correlation detection technology to obtain the characteristics of the stable phase travel time change of e...On the basis of the airgun source signals recorded by the stations from January,2016 to June,2017,we use cross-correlation detection technology to obtain the characteristics of the stable phase travel time change of each station.We used the Yunlong MS5.0 and Yangbi MS5.1 earthquakes as samples.According to regional characteristics,13 stations with high signal-to-noise ratios and complete data were selected(including 3 fixed stations and 10 active source stations).They are divided into four regions,and on the basis of the GNSS baseline data,the characteristics of regional wave velocity changes before and after the earthquake are analyzed.The results show that the station phase travel time change and the regional stress characteristics represented by the GNSS baseline data have good correlation in the short-term.Due to different degrees of regional stress,there are differences in the travel time changes of different stations in the four regions.Before the Yunlong MS5.0 and Yangbi MS5.1 earthquakes,with regional stress adjustment,there is an upward trend in the travel time changes of related stations in the adjacent areas of up to 0.02 s.The difference is that there are differences in the time nodes and duration of the travel time anomalies,and there is a reverse descent process after the Yangbi MS5.1 earthquake.There are different degrees of travel time fluctuations in the relevant stations before and after the two earthquakes,but the fluctuation range before and after the earthquake was small.Compared with the water level change of the reservoir,the adjustment of the regional stress is more likely to have a substantial impact on the travel time changes of the relevant stations.展开更多
基金supported by the Director Foundation of Institute of Seismology,China Earthquake Administration(201326123)the National Natural Science Foundation of China(41204058,41474064)the Ministry of Science and Technology major instrument special sub topic(2012YQ10022506)
文摘The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations one month before the Leshan M5.0 earthquake.
基金Supported by the Earthquake Science Foundation Project of Earthguake Administration of Xinjiang Uygur Autonomous Region ( 201112)the Program of Earthquake Risk Assessment on Actine Faults in Key Monitoring Region of China ( 2200409)
文摘The epicenter of the M5.0 earthquake occurring in Jinghe County, Xinjiang on October 16, 2011, is located in Tuoli Township. The intensity of the meizoseismal area is VI. The seismic damage investigation shows that the houses are mainly mud-clay style and the seismic damage characteristics take on an obvious regional nature. The damage degree varies relative to the field conditions.
基金sponsored by the Yunnan Youth Seismology Science Fund Project(2018k08)the National Natural Science Foundation of China(41574059,41474048)the Science and Technology Special Fund,Yunnan Earthquake Agency(ZX2015-01,2018ZX04)
文摘On the basis of the airgun source signals recorded by the stations from January,2016 to June,2017,we use cross-correlation detection technology to obtain the characteristics of the stable phase travel time change of each station.We used the Yunlong MS5.0 and Yangbi MS5.1 earthquakes as samples.According to regional characteristics,13 stations with high signal-to-noise ratios and complete data were selected(including 3 fixed stations and 10 active source stations).They are divided into four regions,and on the basis of the GNSS baseline data,the characteristics of regional wave velocity changes before and after the earthquake are analyzed.The results show that the station phase travel time change and the regional stress characteristics represented by the GNSS baseline data have good correlation in the short-term.Due to different degrees of regional stress,there are differences in the travel time changes of different stations in the four regions.Before the Yunlong MS5.0 and Yangbi MS5.1 earthquakes,with regional stress adjustment,there is an upward trend in the travel time changes of related stations in the adjacent areas of up to 0.02 s.The difference is that there are differences in the time nodes and duration of the travel time anomalies,and there is a reverse descent process after the Yangbi MS5.1 earthquake.There are different degrees of travel time fluctuations in the relevant stations before and after the two earthquakes,but the fluctuation range before and after the earthquake was small.Compared with the water level change of the reservoir,the adjustment of the regional stress is more likely to have a substantial impact on the travel time changes of the relevant stations.